-18% is the change from 939 to 770
Calculation steps:
[( 770 - 939 ) ÷ 939] x 100 = -18%
Formula
Percentage change = [(770 - 939) / 939] x 100
Subtract the new number by the original number
770 - 939 = -169
-169 ÷ 939 = -0.1799787007454739
-0.1799787007454739 x 100 = -18%